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<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport"
        content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>参数默认值</title>
</head>
<body>
  <script>
    //ES6 允许给函数参数赋值初始值
    //1. 形参初始值 具有默认值的参数, 一般位置要靠后(潜规则)
    // function add(a,c=10,b) {
    //     return a + b + c;
    // }
    // let result = add(1,2);
    // console.log(result);

    //2. 与解构赋值结合
    function connect ({ host = '127.0.0.1', username, password, port }) {
      console.log(host)
      console.log(username)
      console.log(password)
      console.log(port)
    }

    connect({
      host: 'atguigu.com',
      username: 'root',
      password: 'root',
      port: 3306,
    })
  </script>
</body>
</html>